In recent years, the glucose metabolism and particularly the treatment of elevated blood sugar values has increasingly become the focus of attention of the persons in authority, owing to the gravity of disorders following in the wake of elevated blood sugar values, and not least also because of the related, immense costs for the healthcare system. Considering the fact that the glucose metabolism is as yet not fully understood, it is not surprising that new study protocols on the future scientific investigation of glucose metabolism are being regularly published up to the present day, as again recently in the congress paper “Glucose Uptake and Elimination Following an Intra-Dialytic Glucose Load” by Giessauf et al. on the occasion of XLIV ERA-EDTA, Jun. 21 to 24, 2007, in Barcelona, Spain.
Diagnosis of a manifest diabetes mellitus is nowadays possible in a comparatively simple manner. What presents more difficulty is to furthermore recognize preliminary stages of a diabetes mellitus not clinically manifest yet, that are accompanied by an impaired glucose tolerance.
From practice, methods for the determination of a person's glucose tolerance and/or insulin resistance are known. These methods serve for the recognition and differentiation of an impaired glucose homeostasis (“impaired fasting glucose”) or of a diabetes mellitus, respectively. To this end, blood parameters are initially determined for the person in question. Based on the measured blood parameter values on the one hand and the entirety of circumstances that might jointly have influenced the measurement values on the other hand, the physician may diagnose a possibly existing impaired glucose homeostasis.
The circumstances that must not be left out of consideration in such a diagnosis include, inter alia, whether the patient had been fasting or post-prandial at the time when the blood sugar values were taken, how much time had passed since a glucose administration for testing purposes, whether the patient is running a temperature, whether the patient ingested a minimum amount of carbohydrates over the past few days, and whether the patient is on medication.
In case of medicament ingestion, those medicaments which are apt to influence the blood sugar level are particularly of relevance. Such medicaments include, e.g., corticoids, contraceptives, or oral antidiabetics. But the physician also has to elucidate whether, e.g., insulin other than endogenous insulin was administrated. Such intake not in connection with a prescription by a physician may regularly be observed with persons having an explicit desire to lose weight. Lastly, the circumstances to be taken into account by the physician when diagnosing a pathological glucose tolerance also include disorders that have a bearing on the production or secretion of insulin.
The blood sampling necessary in the performance of a glucose tolerance test following oral intake of glucose is felt by some patients to be unpleasant.
As diabetics are, as a general rule, also dialysis patients as a consequence of their sugar metabolism, it is proposed in PCT Publication No. WO 98/19592 to perform the blood glucose or blood sugar level measurement during one dialysis session by way of the dialysis apparatus. As an access to vessels of the patient's has in any case already been placed for the purposes of the dialysis treatment, it is possible to determine current blood sugar values through the method described in PCT Publication No. WO 98/19592 without separately having to take blood for this purpose.
A pathological glucose homeostasis in which the blood sugar values may be measured to be bordering on the hazardous cannot, however, be identified by the method described in PCT Publication No. WO 98/19592. Performance of a dialysis, which results—and is intended to result—in a modified composition of the blood to be treated, may moreover have a negative influence on the blood sugar measurement and result in inaccuracies of the measured blood glucose values.
The present invention has the object of providing an improved method for examining a patient's sugar metabolism and particularly for the determination of characteristic figures relating to the patient's blood sugar, as well as a corresponding apparatus.